1. Field of the Invention
The present invention relates to vessel brought forward in a fluid medium meeting a resistance of flow due to friction against the surrounding medium, and other marine constructions which at least partially reach under the surface of water. Especially, the invention relates to coatings below the surface of water for anti-fouling and reducing friction.
2. State of the Art
Vessels of the abovementioned type are floating in or supported by a surrounding medium both when they are stationary and moving forwards. Vessels also encounter a powerful resistance of flow when driven forwards, the resistance increasing with the square of the speed as it increases. The resistance to flow depends mainly on the friction against the surrounding medium and the greatest part of the input energy to the vessel is consumed for overcoming this frictional resistance. In order to reduce this resistance of friction and flow, up to now vessels have been made streamlined and the surfaces facing the medium as even and smooth as possible. One has also tried to paint the surfaces with friction reducing means and used toxic paints for preventing overgrowth and thereby increasing resistance of flow.